Thank you Tom and Gail.

I just did some experiment, and I think one point I didn't make it clear. I said earlier one server is dev, the other is production.

Actually, it is not production, it is a copy of database I restored from production to my local. I wanted to test that before I run the second load on prod, so I restored the db from prod to my local to do the second load.

Somehow I think just because this is a restored database, it makes the difference.

when I do the second load to the table on my local, it starts from 5000000 instead of 5000001. it will start with the seed instead of seed+1 even it has records in it.

Then I did another experiment to create a simple test database with a couple of records in the table. Then restore it, then load with new data with seed, it proves above theory.

Also thanks Gail, it is good to know it does not matter the key start with. I thought it is better to make dev enviroment and prod the same starting number, maybe easier to troubleshoot for later.

Thanks,